NEW YORK (Reuters Health) - Injection drug use appears
to be the leading cause of hepatitis C virus (HCV) infection in
patients with HIV, Swiss researchers report in the August issue of
Clinical Infectious Diseases.

"The continuing high incidence in injection drug users," senior
investigator Dr. Hansjakob Furrer told Reuters Health, "is
disappointing because it reflects our inability to reach this
population sufficiently, even in a country with a high standard of
needle exchange and substitution programs."

To investigate the relative roles of injection drug use and unsafe
sex in spreading HCV, Dr. Furrer of University Hospital Berne and
colleagues studied data on 7889 HIV patients. Between 1998 and 2004,
the seroprevalence of HCV was 33%. However, it was 90% in those
reporting injection drug use.

The overall HCV incidence was estimated to be 0.64 cases per 100
person-years. In participants with a history of injection drug use, the
incidence was 7.4 cases per 100 person-years compared to 0.23 cases per
100 person-years in those without such a history.

In men who had sex with men (MSM) who had no history of injection
drug use but who did report unsafe sex, the incidence was 0.7 cases per
100 person-years. In men who did not report unsafe sex, the incidence
was 0.3 per 100 person years.